Optical Processing Using Degenerate Four-Wave Mixing

Sami A. Shakir

Pedro Enrique Piñeros Lourenço

Antonio Mecozzi, P. Spanò, Alessandro D’Ottavi +1 more

Degenerate Four Wave Mixing (DFWM) and Nearly Degenerate Four Wave Mixing (NDFWM) have attracted a considerable attention in non-linear optics. DFWM has found several applications in phase conjugation, used in real time holography and adaptive optics. To realize a higher amplification of the conjugate wave, semiconductor amplifiers have been used. A theoretical analysis of the NDFWM process has been presented by Agrawal [1]. Here, an experimental and theoretical analysis of NDFWM in Distributed Feedback (DFB) lasers is proposed, where the FWM efficiency is enhanced by the cavity feedback mechanism.

Alexander L. Gaeta

Herbert G. Winful, John H. Marburger

The intensity-dependent refractive index leads to hysteresis and optical bistability in degenerate four-wave mixing processes (DFWM). Bistability may be observed in the phase conjugate signal or in the ’’spontaneous’’ oscillation possible in DFWM. This bistability does not require external resonant cavities.

Chengjie Zhu, Yan Li, L. Deng

Highly efficient, optical-degenerate wave-mixing involving bosonic quantum gas is studied using a crossed-beam geometry. We show a very large enhancement due to nonlinear gain from a matter-optical wave-mixing process involving four photons and two matter-wave excitations. Under suitable conditions with a red-detuned pump field this optically degenerate, four-photon process can be stronger than the traditional two-photon inelastic light-scattering mechanism, leading to strong nonlinear growth of the observed matter-wave scattering. This optically degenerate four-wave mixing is independent of other enhancements arising from bosonic stimulations. More importantly, this highly efficient, backward degenerate wave generation and growth process does not have a correspondence in thermal gases in nonlinear optics.